The plugin is a work in development by a non-Mozilla employee at the moment - me Just a bit of a pet project. It's in need of a good test, some general improvements and some core code additions (as you've noted) and I've just not really gotten around to having the time to get back to it for a while really.

Ideally I want to submit it to contrib but as it currently requires additions to core code I'm trying to figure out if those can be adopted in as improvements so that the plugin itself will work as it should without the additional need for core changes per install.

I popped up a couple of tracker items for some of those things and am slowly working on them in little ways. One almost made it to integration but needs some more refining and the other has been rejected as the authentication plugin is apparently going to be re-worked and so no new functionality is going to be accepted before then. Unfortunately, the details on the rework or the timeframe for that haven't been determined yet so it's a waiting game and the work around I've made at the moment may then also need to be adjusted depending on what this does.

2. New Authentication plugin functionality for adding Javascript to the page where the login_info block is located. This is so that the hook can be triggered succesfully. I can't seem to find a related tracker item for this but it is the before_logout hook commit in my github dev branch (see the bottom of this post).

3. An improved Authentication plugin function for printing IDP elements on the login page. Currently the IDP function is hardcoded pretty restrictively and plugins themselves cannot determine how they actually want to display. I broached the issue here but it's been rejected due to th e aforementioned rewrite etc https://tracker.moodle.org/browse/MDL-38976 I would like to submit to them a smaller patch that just adds in the new potential IDP function that'd increase flexibility rather than the entire rewrite (obviously) so hopefully that'd be easier to be incorporated.

In it's current core state that function is particularly restrictive.

I have a development branch on my github too that I was trialling some of these requirements. As you can see though it hasn't been updated against core code for a while.

Let me know if you have any other issues and I'll try to help you out with it. As I say it needs a good test s it's not really ready for release so I'm glad someone is interested in it! I do know of at least one existing bug and I certainly am not finished with the overall design yet - any feedback and ideas are welcome.

Sorry for the delayed reply, I will wait with anticipation. Persona never seemed to be high on the list which is unfortunate. With the release of Moodle 2.5 and Badges as native Persona may have found a place. I like it for that reason and also because it is a poor man's SSL.

I'm definitely keen to help the Mozilla team get more coverage by enabling more sites to use it so hopefully once I get more time I can look at trying to help the Auth team with the other items and try and get it included in a later release of Moodle. In the mean time if you do manage to play with it with my patched branch do let me know about any issues or suggestions you might have and I'll add them to the list of things to do for it.